1. w/o Navigation system: INSPECT ILLUMINATION OPERATION
(a) Connect the positive (+) lead from the battery to terminal C10 and negative (-) lead to terminal C19, then check that the indicators illuminate.
If operation is not as specified, check the faulty bulb.
(b) Remove the bulb.
(c) Using the tester as shown in the illustration, test the continuity.
If continuity exists, replace the heater control.
If no continuity exists, replace the bulb.
2. w/o Navigation system: INSPECT INDICATORS OPERATION
(a) Connect the positive (+) lead from the battery to terminal C22 and negative (-) lead to terminal C12.
(b) Check that the indicators come on while operate the switches.
If operation is not as specified, replace the heater control.
3. INSPECT A/C CONTROL ASSEMBLY CIRCUIT (DI-1309 )
4. w/ Navigation system: INSPECT ILLUMINATION OPERATION
(a) Connect the positive (+) lead from the battery to terminal A8 and negative (-) lead to terminal A16.
(b) Check that the indicators come on while operating the switches.
If operation is not as specified, replace the heater control.
5. INSPECT A/C CONTROL ASSEMBLY CIRCUIT (DI-1309 )